Enhancement of the rate of the beta-elimination of phosphate from radicals derived from glycerol-2-phosphate by Cu(I)-phenanthroline. A pulse radiolysis study.
Hydroxyl radicals abstract hydrogen atoms from glycerol-2-phosphate with a specific rate constant of (7.0 +/- 1.5) x 10(8) M-1s-1 forming the beta-phospho radical as the major product. At physiological pH this radical undergoes a beta-phosphate elimination with a rate constant less than or equal to 1 x 10(3) s-1. The beta-phospho radical reacts with Cu(I)-phenanthroline to produce an unstable transient with a metal-carbon sigma-bond which has an absorbance similar to that of the cuprous phenanthroline complex in the visible region. This intermediate decomposes via a beta-elimination of phosphate with a rate constant of (1.0 +/- 1.5) x 10(4) s-1, which was independent of the acidity in the pH range 4-9.
Goldstein
S
S
Department of Physical Chemistry, Hebrew University of Jerusalem, Israel.
Czapski
G
G
Cohen
H
H
Meyerstein
D
D
D004249:DNA Damage; D005609:Free Radicals; D005994:Glycerophosphates / Q000737:chemistry* / Q000528:radiation effects; D007700:Kinetics; D008956:Models, Chemical; D010618:Phenanthrolines; D010710:Phosphates; D011675:Pulse Radiolysis
D005609:Free Radicals; D005994:Glycerophosphates; D010618:Phenanthrolines; D010710:Phosphates; C025205:1,10-phenanthroline; C031463:beta-glycerophosphoric acid